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When to Plant Sunchoke in Wharton County, TX

Sunchokes (Jerusalem artichokes) are a native sunflower relative grown for their knobby, nutty-flavored tubers. They are extremely productive and nearly impossible to eradicate.

Wharton County, Texas is in USDA Zone 9a. The average last spring frost is February 17 and the first fall frost is December 6, giving you a growing season of approximately 292 days.

At an elevation of 207 feet, Wharton County receives approximately 64.8 inches of rainfall annually with predominantly loam soil. Summer highs average 98ยฐF, so Sunchoke may need afternoon shade and extra watering during peak heat. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Sunchoke root diseases.

Wharton County, TX (Zone 9a) Year-round
292 days
Last Spring Frost February 17
292 growing days
First Fall Frost December 6

Wharton County Soil Profile

Soil Type

Loam

Soil pH

6.6-7.7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (113 days to spare)
Transplant: Feb 19 🍅 Harvest: Jun 11 – Aug 6
Recommended (50%) ✓ Fits season (110 days to spare)
Transplant: Mar 3 🍅 Harvest: Jun 23 – Aug 18
Safe Start (90%) ✓ Fits season (102 days to spare)
Transplant: Mar 26 🍅 Harvest: Jul 16 – Sep 10

Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.9″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 185 gal / 100 sq ft
Sunchoke needs ~3,055 GDD — county provides 6,885 GDD Excellent fit

Sunchoke Planting Timeline โ€” Wharton County, TX

Sunchoke Planting Calendar

Activity When Date Range
Transplant Outdoors March 3 Mar 3 โ€“ Mar 17
Harvest June 23 Jun 23 โ€“ Aug 18

Plant 1" deep ยท 30" apart ยท Rows 42" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March Transplant Outdoors
April โ€”
May โ€”
June Harvest
July Harvest
August Harvest
September โ€”
October โ€”
November โ€”
December โ€”

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

Moderate โ€” regular watering

Days to Maturity

110โ€“150 days

Soil pH

6 โ€“ 7.5

USDA Zone

Zone 9a

Growing Season

292 days

Growing Tips for Wharton County

Plant tubers 4 inches deep in early spring. Contain plants with barriers as they spread aggressively. Harvest after frost or leave in ground and dig as needed through winter.

Companion Planting

Good Companions

Level Up Your Garden

Frequently Asked Questions

When should I plant Sunchoke in Wharton County, TX?

Wharton County is in Zone 9a with an average last frost of February 17. Plan your Sunchoke planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Wharton County, TX?

Wharton County, Texas is in USDA Hardiness Zone 9a. The average last spring frost is February 17 and first fall frost is December 6.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Wharton County gardeners in Zone 9a organize planting dates, track what's growing, and never miss a planting window.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Wharton County, TX. Local conditions may vary. Last updated: April 2026.